This disclosure relates to gas turbine engines, and more particularly to turbine rotor components. In particular, the present disclosure relates to turbine airfoils and methods of cooling turbine airfoils.
Turbine airfoils or outer air seals operate in an environment where the associated gas temperatures often exceed the capability of the materials of the airfoils and/or outer seals and therefore they require cooling features to protect against damage. Cooling air from a compressor of the engine is directed towards these surfaces and provides internal convection cooling inside the airfoils. One side effect of directing large amounts of cooling air towards these surfaces or components is that less gas then becomes available for work extraction and therefore, the overall engine efficiency may be reduced with higher amounts of cooling. In addition, blade tips are highly susceptible to erosion, oxidation, and thermal mechanical fatigue crack damage due to high thermal heat load. This damage reduces turbine efficiency by increasing cooling leakage air. As demands for higher thrust or efficiency increase, the airfoil design must accommodate for increasing turbine inlet temperatures and/or reduced cooling flow allocation.
Accordingly, it is desirable to provide turbine airfoils with improved cooling features and methods of cooling areas of the turbine airfoils.